The Anti-Tumor Effects And The Mechanism Of Arsenic Trioxide (AS₂0₃) On Transplanted Tumor Of Human Endometrial Carcinoma Cell Lines (HEC-1B) In Nude Mice

Objectives. To examine the anti-tumor effects of arsenic trioxide (As2O3) on transplanted tumor of human endometrial carcinoma cell lines (Hec-1B) in nude mice and investigate the mechanism of th action.Methods. The nude mice with transplanted tumor of endometrial carcinoma cell lines (Hec-1B) were randomizated to 5 groups, And they were treated with NS, DDP, increasing concentrations of As2O3 (lmg/kg,2.5mg/kg,5mg/kg) through inter-abdominal cavityinjection. To detected the respects to cytotoxicity and the induction of apoptosis detected by flow cytometry and caspase-3 expression detected by real-time PCR and p-ERK expression used of Immunohistochemical technique in vivo.Results. Compared with the saline group, As2O3 and DDP significantly inhibited the growth of transplanted tumors and induced apoptosis in nude mouse vivo. The inhibited cell rate on As2O3 (1.0mg/kg) group is 34.3%, and its expression rate of p-ERK is 37.5%, the relative expression of Caspase-3 is 1.63, and the typical sub-G1 peak emerged in this group. The apoptosis and tumor mass of As2O3 (1.0mg/kg) group were significantly different with the saline group. As2O3 also showed less hematological, hepatic and nephritic toxicity than DDP.Conclusion. As2O3 may exert anti-tumor effects through the induction of the apoptosis pathway. And increasing caspase-3 may play an important role in the anti-apoptotic effects and inhibiting p-ERK may obstruct the signal transmition in the MAPK pathway which are observed when endometrial cancer cells are treated in vivo with As2O3.